00 [Cities 1.5 Main Theme plays] I'm David Miller and you're listening to Cities 1.5, a podcast about how climate leaders are driving global change through local action. [urgent music] Heading into the COP28 UN Climate Change Conference last fall, the world teetered on a knife edge. Hopes for a positive outcome were low when it was announced that it would be held in the United Arab Emirates, a petrostate whose economy is heavily dependent on the extraction and export of oil and gas.
As the conference unfolded, the record numbers of fossil fuel lobbyists in attendance drew the ire of climate activists from across the globe. Many prominent climate figures and key players were conspicuously absent, thinking that it wouldn't be worth the effort or the emissions to attend. Despite these obstacles and misgivings, COP28 ended with an historic first. After dramatic, intense negotiations lasting deep into the night, a road map to transition away from dirty energy was agreed upon.
Could the end of the fossil fuel era finally be within reach? [music fades out] [gentle, delicate music] COP28 also saw the first global stocktake of the 194 national governing bodies and the European Union, who adopted the Paris Agreement. In 2016, the parties all vowed to meet targets which mitigated emissions and adapted to climate impacts. Achieving these goals is vital if the world is to keep global heating under 1.5˚C degrees above pre-industrial levels. The result?
The parties nationally-determined contributions are woefully lacking. The world is officially and dangerously off track. [upbeat, energetic music] For the first time ever, cities and their mayors had a seat at the table at COP28, solidifying their status as climate leaders. Over 70 countries committed to working with local leaders on the next round of nationally-determined contributions for 2025.
75% of C40 cities, many of whom were present at COP, are reducing emissions faster than their respective national governments. While the actions of cities and mayors from across the world give all of us hope for the future of our planet, more is needed from national governments and industry if we are to avert catastrophic outcomes such as the collapse of polar ice sheets, fatal health impacts of dirty air, and the ravages of storms and wildfires. The window for action is rapidly shrinking.
Now that the dust has settled from COP28, we're just over five years away from the next crucial climate deadline – 2030. So, where exactly does the world currently stand? [music fades out] [upbeat electronic music] In today's episode, we'll hear how one of the world's leading human ecologists is rethinking humanity's densest habitats, how net-zero innovations are transforming the places we live into sustainable eco-cities, and how the world can avoid triggering deadly climate tipping points.
But first, let's get the inside story on the progress and influence cities and mayors had at COP 28, and what the coming years might hold for the world's urban centres and their leaders. [music fades out] [rotary dial telephone rings] [clicks] Hello I am Mark Watts. I am the Executive Director of C40 Cities and I am dialling in today from the wonderful city of London. [receiver chimes, replaced in cradle]
07 Mark Watts has served as the Executive Director at C40 for over a decade. Under his tenure, C40 has led the way through being the first organization of governments to adopt the 1.5°C target, which aims to halve global emissions by 2030. By increasing coalition building with civil movements, unions, businesses, and youth climate leaders, Mark and C40 have delivered both bold ambition and bold action. [music ends] Mark, welcome to Cities 1.5.
41 Hello. Delighted to be joining.
44 Can you just tell our listeners a little bit about yourself, your background, and what inspired you to work in the climate sector?
52 The true answer for how I got involved in working on the climate crisis is because I was told to.
My then-boss, the then-mayor of London, Ken Livingstone, I used to do a thing for him when I was one of his researchers; I would take books away at the weekend that he didn't have time to read and then give him a précis on them and, one weekend, he gave me Jared Diamond's book, Collapse, to read, which is an anthropological study of how civilizations throughout history have either survived or failed, depending on whether they could live in harmony with their environment.
I read that, summarized it, and I remember the mayor asking me, "Are you terrified after reading that?" and I said, "Yes. Yeah. [chuckling] I really am. Yeah. This climate crisis thing seems a real problem," and then he said, "Good. You're now my climate advisor." So, that's how I got into it.
36 So, it does raise an issue that I hear often when I speak, Mark, or do a promotion session for my book, Solved; people say, "Why cities?" You've been involved in this space as an advisor to one of the great mayors of one of the world's great cities, and now leading C40 as an organization of mayors of the world's greatest cities – nearly 100 of them. Can you just speak to that? Why do cities matter to addressing climate change? And, in particular, why does C40 matter? Who is it?
And why does it make a difference?
11 Well, you know, the obvious answer to that is just cities are where most people live and its most energy is consumed there, and they're where most carbon emissions are produced.
But, actually, I think the more important thing—that more interesting thing, and certainly it is why C40 has an important role—is because the only way of tackling climate breakdown is through incredibly extensive global collaboration and cooperation that transcends political differences, geographic, cultural boundaries, and what the leaders of cities—the mayors of cities, the governors of cities—have really demonstrated a propensity to do over the last couple of
decades is to build that type of global collaboration, to come together on a common problem of the climate crisis and not to compete with each other or wait for each other to go first and only be willing to do the difficult things if someone else has done it, but instead to help each other to all move much faster.
And really, for me, the inspiring thing about working with mayors and the reason why I think C40 has got a big role to play is it shows what is possible, that could happen at other levels of government and across the private sector, across civil society, the way that we could collaborate globally to overcome the climate crisis.
23 You've just come back from COP28 in Dubai. Can you speak about that in the context of what you just said – that cities systematically have been collaborating, not saying, "I'm not going to do anything until you do," about saying, "How do we do it? How do I learn from you? How do we address this challenge?”
45 It was a historic COP from the point of view of, I think, marking the start of a significant shift in who's at the table to make these annual climate talks a success. They've been set up to essentially be a negotiation between the national governments of the world and, frankly, without a lot of success. We've had a couple of moments – the original founding of the Paris Agreement. Hard to point to much else, really. Kind of slow, incremental negotiated progress for global solutions.
What you saw at this COP was, for the first time, a major space being created inside the so-called "blue zone" – the place where you've got to have a pass to get in, to be alongside the presidents and the prime ministers and the ministers, a stage for mayors and for governors of regions, so states in the US, etc. I thought that really galvanized the whole process because you had a very big group—hundreds of powerful political leaders—who are really working together
and very dynamically trying to bring down their emissions and achieve resilience against the ever-growing impacts of climate change without any mention of agreements, dots and commas, clauses in the right place – just talking about the action that they were taking and how they could move faster if they got greater support from each other, or if their finance was flowing in bigger and faster to the to the right places.
And I think this is the start, hopefully, of a changing of the nature, coupled together... We've seen, in the past, that first step of bringing in civil society, business, NGOs like C40, to get a positive pressure onto the COP, but this is the first stage in formalizing that.
33 [driving music] Well, it's a big victory for C40 to be part of the movement. Much congratulations on that. That's a positive outcome and achievement of this COP. There was quite a bit of criticism, for example, of some of the comments that the COP president made at one point in time during the conference. Yet, the final statement perhaps was a cause for optimism. There did seem to be a hint of progress in the final communique.
00 There was definitely progress in the painfully slow world of climate negotiation – quite important progress because, for the very first time, there was recognition—the agreement at the end of this COP—that we need to stop using fossil fuels. And, it's extraordinary that it's taken to COP28 to get there. So, all the agreements should be about abating carbon emissions.
[music fades out] They hoped and expected and invested a lot of lobbying effort in trying to achieve that so, in that context, to have instead, for the first time, got a recognition and agreement across all the nations that we need to stop using fossil fuels was indeed progress, and the UAE deserves some credit that that, as also for creating the space for the non-state actors to be very centrally in the process.
And then, you know, the good stuff that was at COP about the investment to treble in this decade, that's really where we need to go now. And, in that context, you know, clearly it was a huge error by the COP president to make those false comments that science doesn't require a phasing out of fossil fuels.
05 So, the door has been opened for the first time for this conversation about the phasing out of fossil fuels and, as you noted, it's really urgent.
Certainly, the global stocktake showed us that we're not nearly making remotely enough progress so, from your perspective as leader of this city-based organization whose mayors represent urban regions of at least 700 million people—it's like a giant country—from that perspective, now that there's a recognition of what the problem actually is, where does the world go now? What's the role of cities?
And, what's the role of C40, both from an action perspective and an advocacy perspective to drive the change that's needed?
54 Well, I think where it has to go, for national governments, but actually for all actors—for big businesses, for cities, for regions now—is to do exactly what C40 Cities started doing immediately after the Paris Agreement, which is put together a very clear action plan for what it's going to take and how you're going to achieve making your contribution so the world stays under 1.5˚C, because there is absolutely no way we can make the extraordinary scale of change that
is necessary to achieve that goal and, at the same time, improve our resilience to the impacts that are already happening without some really serious planning, because you've got to map out,—and at a very sort of systems level, across cities, regions, countries—how you're going to deploy resources to make a change to our energy system and, in fact, a change to our entire economies, at a pace and scale that's never been achieved before in human history.
What C40 mayors did, coming out of the Paris Agreement was exactly that. We sat down as the professional team with the leading mayors and said, "Okay, the world has now agreed we're going to stay under 1.5˚C. This is a massive step forward. If we're serious, we've got to show how we're going to do it," which means a thorough, robust plan for each city, based on some international standards which we created.
A condition of being a member of C40 is to have that plan and be implementing it and be measured on it on an annual basis. That's what we've been doing.
Now, the focus – the national governments need to shift to that the revision of their NDC—their Nationally Determined Commitment on climate—that, under the Paris Agreement, has to be delivered by 2025, and we need all of those to now be consistent with the world halving the use of fossil fuels this decade and cutting emissions fast enough for the world to stay under 1.5˚C.
40 2025 is a key date. 2030 is another one. The C40 plans you referred to, Mark, as we both know, require our cities to do their fair share of the overall halving of global emissions—more or less halving—that's required by 2030. What do you see as the key climate battlegrounds ahead of 2030, and what can C40, the world's great cities, other cities and mayors do to ensure that those battles are won?
13 [light, percussive music] Deadlines – to have that focus on the next five years, the next decade rather than the mid-century 20, 40 years. Unfortunately, it's taken that we're now really, really in the crisis of climate breakdown to bring that focus much nearer. There are some really simple answers to this. Number one – as the International Energy Agency has been saying for a few years now, we've got to stop all new investment in fossil fuels.
There is no place for investing in trying to pull more oil and gas. [music fades out] And then, you know, equally importantly, really putting the focus and an investment on how we can rapidly change our economies to be fundamentally clean, in terms of energy resource efficient, but also much more equitable to do that in a way where there's a transition in which those who are currently most vulnerable and get the least out of the global economy see their standard of living rapidly rising.
And clearly, someone's going to have to pay for that – that those who are currently most privileged are producing the most emissions and cause most of the problems are going to have to contribute a bit more to make that possible. But, in the end, we all win because we get a future where all of us can thrive and can live better lives.
The role for cities in this, I see, in the immediate period, is really about reducing the demand, because I've seen nothing in my career that suggests that the finance sector is going to lead and, out of altruism, is going to say, "We're gonna stop investing in fossil fuel." What's going to turn off that tap is that the demand starts to come away.
So, when mayors take really tough decisions to bring in clean air zones that restrict polluting vehicles from traveling within the city, that starts to cut off the demand – the petrol for gasoline.
When they regulate to change what kind of buildings are permitted and the energy systems that serve them, so investing in regulating out highly-polluting cooking stoves, charcoal, etc., and replace it with clean renewable electricity, in African cities, for example, those things again, they cut off the demand for those fossil fuels and they start to make that investment prospect for oil and gas and coal far less sound.
On the positive side, we've really seen a massive, massive increase in investment in renewable energy, primarily driven by China. Half of all the world's investment in renewables is in China and, similarly, a huge, huge, huge shift to electric vehicles, which is a significant part of the global emissions is in transport which, I think, gives us the tipping points for the global economy are achievable.
03 It seems that, even when national governments have tensions, cities are able to have conversations about real and substantive issues between themselves, regardless of the geopolitical situation, which really seems to add to the ability to spread these solutions.
19 I was very pleased to see that very evidently, that 15-minute city concept, the urban development, is China learning primarily from European cities, but there are examples all over the world now – clean construction standards that they're adopting, coming very much from Vancouver, from Oslo, and a lot of interest around budgeting at a city level, which, David, you and I have both been big advocates of, coming from other cities across the world.
43 One of the examples I'd be interested to hear your thoughts about is shipping. There's work going on, led by Shanghai, Los Angeles, and I think Copenhagen.
53 The stuff around the green ports and green shipping was really fantastic because this is an initiative that was seeded by our former chair, the incredible Eric Garcetti—formerly Mayor of Los Angeles, now U.S. ambassador to India—and he had this concept of, if we're going to change one of the hardest-to-move sectors, the shipping sector, off fossil fuels onto renewables, then the best way for that to happen is if ports, and the big cities that regulate or own them,
get together and let's create a green shipping corridor between two of the biggest ports in the world—Shanghai and LA Long Beach—and, that is now happening.
In addition to that collaboration, there's now a collaboration between Singapore and Long Beach, starting, to kick off, and I saw in Shanghai—I mean, it's all a bit kind of sci-fi—but the largest port in the world, the newest bit of a quarter of which has now been fully electrified, so meaning that these huge great container ships aren't running their great big diesel engines, polluting the city when they're in port, but instead, are plugging in—clean electricity
takes huge amounts of infrastructure to provide the kind of power that they need—but also, a fully automated port. The whole automated process has allowed it to maximize the efficiency and therefore make it cost effective to run it in a much cleaner fashion. And, if that's happening end to end in LA to Shanghai, two of the biggest ports, we're going to see a lot more following suit, and already, I know there are many other ports looking to do the same thing.
29 [pensive music] Well, there's some cause for optimism from China, there's cause for optimism from COP28, and even more so, there's cause for optimism from the great work of mayors and cities around the world. And, we've got pretty tough deadlines.
2025 is next year, 2030's six years, and, you know, you're leading a critical part of this climate movement, and I think all of our listeners wish you luck and success to move from optimism to building on the real action that cities are taking today.
03 Well, thanks so much, David. I've really enjoyed this conversation. It's a real honour to work in this sector because it provides the opportunity to be optimistic.
10 Thanks again for your time today.
12 Thank you. [music continues then ends]
21 [light, driving music] This episode of Cities 1.5 is produced by University of Toronto Press with generous support from the C40 Centre for City Climate Policy and Economy. Want more access to current research on how city leaders are taking climate action? We also publish the Journal of City Climate Policy and Economy. Our mission is to publish timely, evidence-based research that contributes to the urban climate agenda and supports governmental policy toward an equitable and resilient world.
The Journal serves as a platform for dynamic content that highlights ambitious, near-term climate action, focusing on human-centred solutions to today's most pressing climate challenges. To read the latest issue, visit JCCPE.utpjournals.press or find the link in the show notes.
01 [rotary dial telephone rings] [clicks] My name is Xuemei Bai, distinguished Professor in Urban Environment and Human Ecology, Australian National University. I'm sitting here in Canberra. [receiver chimes, replaced in cradle]
34 [upbeat electronic music] Xuemei Bai is a scientist and academic who has authored over 100 publications, and her accolades are nearly too many to count. She was a lead author for the Millennium Ecosystem Assessment, the Global Energy Assessment, and the IPCC's Sixth Assessment Report. She also co-leads the Earth Commission's Working Group, targeting planetary levels in cities and businesses. [music ends] Professor Xuemei, thanks so much for joining us on Cities 1.5.
10 Thank you, David, for having me here.
11 Your resume is incredible. Can you just speak a little bit so that our listeners can understand the work that you do and your involvement with all these various commissions from the perspective of ecology, human health, and climate change?
27 So, the primary focus of my work has always been urbanization and cities, so I have at least three distinct sort of streams of work. The first one is really looking at the process of drivers and impacts of rapid urbanization, and that includes what that means for global sustainability. And, the second part is trying to really understand various aspects of cities and climate change.
And then, third bit is looking at cities as active and transformative agents for a climate-safe future and global sustainability. So, those are the things that I do here at the Australian National University.
04 Well, I think all three of them have a place in our conversation because rapid urbanization can be done in a way that is supportive of environmental goals or really hurts environmental goals, as we've seen, you know, in the United States, for example, with urbanization that we would loosely call sprawl as a type in many, many cities. A lot of the science about climate change is thinking about worldwide impacts or looking at statistics, for example, on a national level.
What's the place, from a scientist's perspective, of urban areas and cities in that conversation?
46 Well, urban areas and cities are absolutely playing a crucial role in this whole thing. For example, just look at the current impact that cities are having. The most recent IPCC report shows that almost up to 80% of all consumption-related GHG emissions actually can be traced back to cities, so we know cities are already making a huge impact in terms of causing this current climate change. And, the second one is we really need to look at the future impact, right?
The UN population projection actually shows that about two billion more people will be added to the world's cities, and then about 90% of them will be added to the cities in developing countries. So, these new urban residents, they will require housing and infrastructure if they are to have a decent urban life, and that's what we want.
If we are to provide the same level of infrastructure services to those people in developed country's cities, and do it in a business-as-usual way, our analysis actually shows that may entail 226 gigatons of carbon emissions, and we all know that, from the most recent IPCC report, it says the remaining carbon budget, if we are to achieve the 1.5 degrees, is about 420 gigatons of CO2.
So, we can see, building these new cities and then providing services alone, will, you know, just blow more than half of the remaining carbon budget, and this really means that we really certainly need to find some innovative ways to build our cities. And also, thirdly, I think cities are really important because of their agency – the potential for them to be active and transformative actors. And, we have really seen this at work.
We already know that cities are often prompting national governments to follow, and we have seen that, for example, like in Korea or in Japan, where the national government committed to net zero only after most of their major cities have already committed to it. Cities can play a significant role in there.
51 As you just said, a huge proportion of the greenhouse gases can be attributed to the world's cities. The world's cities have agency and there are excellent examples of them leading their national government but, at the same time, there is this mass push to build new cities to meet a growing population in many countries of the world. It's a huge challenge to build those cities in a way that is truly environmentally sustainable.
Do you have any thoughts or, as your research indicated, any paths, whether it's cities using their own agency or learning from others, that would help square that circle so that we can anticipate a future that lives within planetary boundaries?
39 [driving music] I would never say "impossible" [chuckles lightly] because that's not only unacceptable but also it's not good for my own, you know, mental health. So, I always like to maintain a positive outlook and really strive towards it. And, we do see a lot of positive signs if we work on cities. For example, many cities have already achieved 100% renewable energy supply.
And then, now we are really looking at how to reduce transportation emissions and also reduce the solid waste management-related emission. So many, many cities in the world are really doing lots of things, starting from what they can, in order to bring about positive change.
19 You followed COP28 very closely. How did you feel when you read or heard that the president of COP28 said that there was no science that said the phase-out of fossil fuels could achieve 1.5˚C, and specifically said there's no road map for a phase-out of fossil fuel that will allow for sustainable socio and economic development, unless you want to take the world back into caves.
49 Well, let me take a deep breath and start from the beginning. [both chuckle] If you look at the IPCC report, it says that limiting warming to 1.5˚C implies reaching net zero CO2 emission, globally, around 2050, right?
And, the report also says that this requires a drastic reduction in fossil fuel consumption, and while there are technically feasible sort of pathways to achieve the 1.5˚C target that includes some ongoing use of fossil fuels, these pathways usually require the use of negative emissions technology to offset those remaining emissions and the feasibility, or the scalability or sustainability of these technologies is unclear and still subject to ongoing research and debate.
[music fades out] So, I think what is clear here is that maintaining fossil fuel use would make it much, much more difficult to get to the 1.5˚C goal and there are certainly, of course, considerable challenges to energy transition to phase out fossil fuel, and actually doing so in a just way.
But what is important is that drastically reducing or phasing out fossil fuel use doesn't really mean that the world has to be set back into caves, and there is increasing evidence that renewable energy is even, economically, more viable than fossil fuel, and many cities have achieved 100% renewable electricity supply, including Canberra, the city where I live now, and we are certainly not back into the caves.
18 You know, the COP president took back his comments a few days later but, to me, they were indicative of a part of the world that looks at things this way and is, you know, usually connected with the fossil fuel industry. Did you have any takeaways from what you saw happen at COP, especially in relation to cities and urban climate action?
43 Well, we can certainly see some achievement, right? For example, like the COP president said, we have the language on fossil fuel for the first time in the Agreement, you know, and that the scale and pace of change can be stopped or reversed.
And then, if I borrow the word of UN Climate Change Executive Secretary, Simon Stiell, he says, "It certainly signals the beginning of the end," but this probably is really far from what the world has been anticipating, and I totally agree with you, David; this really highlights that there is a long way to really, truly mobilize the political will at international and national level, that is required to address this climate crisis.
And, I think, all the more, this means the importance of mobilizing cities to take action ahead of, and really above and beyond, what their national counterparts are really willing to commit. On the other hand, I think it's also very important to not be so naive as to think that actions by cities alone will solve the problem. Cities really need support from the national and their rational government, within, you know, the government institutional structure to fully realize their potential.
But, I mean, cities can really be a very powerful force, both in terms of reducing emissions, as well as taking action, for example, through better spatial planning of cities that require less traffic and enable a public transportation system. And also, to leverage the unique power of cities in shaping a new culture, I think because cities can be really the starter of a new culture and new norms that really says, "Climate-conscious choices are not only necessary but also, you know, cool."
And, I do see cities can play a unique role in this because, traditionally, our cities have really been the birthplace of many such new cultures and new movements. A climate-conscious culture, started in cities can bring about a large-scale change.
43 My instincts are similar to yours, that that cultural change is a very powerful thing, saying, "This is what dealing with climate change looks like." Do you see some big lessons that mayors and their administrations and the cities they govern can take from the leading examples?
00 What I'm really interested in is the potential for collaboration. The first one is city-to-business collaboration. Within our Earth Commission, I've been leading the Working Group that's called Translation, in which we are trying to really connect the planetary or earth system-level target and boundaries down to the actors like cities and businesses.
24 The work of the Earth Commission is really important. Can you just explain, for the benefit of our listeners, what it is and what it does?
29 So, the Earth Commission is a global team of scientists – both social and natural scientists. The focus of Earth Commission is really to answer what are the environmental thresholds that we should not cross in order to safeguard the planet, that can support human well-being, and how can we do it in a just way? So, while trying to do this work, there was a spin-off study that we worked on.
We discovered that many cities that actually have this net-zero target also are those that harm us – really big emitter cities, Global 500 emitter cities. So, what is interesting is that, many of these cities, they have the target, but the companies that are having headquarters in those cities, they don't have net-zero kind of targets, so we really try to look at, what if we can bring those ambitions together?
So, if we do bring those city and business targets to this higher level of ambition, then actually our study shows there is a big additional potential to mitigate the GHG emissions. [gentle music] So, this is something I'm, right now, very much interested in, and we do have a paper that is under review right now.
So, I think it is really important for cities, for example, to really reach out to those major companies that have headquarters in their location, try to have this cross-sector interaction, and then bring everybody onto the journey. Unless everyone, every city, every business is really committed to this kind of goal, then it is not possible for us to collectively achieve this target. And then, the second element of this cross-sector collaboration is city-to-city networks.
If we look at the heightening sort of need for the world to be really prepared for the different kinds of shocks and hazards, almost all the predictions are saying we will be having more and more severe and more frequent extreme weather events, for example, heat waves flood and wildfire, etc. And, we know cities are particularly vulnerable to these kinds of hazards, but the thing is, with the increasing number and frequency of these hazards, it is very, very hard for each and
every city to prepare for each and every hazard that will be coming. [music fades out] So, this really brings me to think about the necessity of trying to build a networked resilience across different cities. So, imagine if we have a group of cities that have formed this kind of network and they can go beyond just sharing information or learning from each other, but really actively plan something and then implement something together in the event of external shocks.
So, if within the network, one city is hit or two cities are hit, there are still many others can actually come to help, and I think this kind of building networked resilience is something that we need to explore, going forward. But, I think most of the focus, for now, is really on sharing information and adopting similar protocol planning – those sorts of things.
So, I would really think the next step for these kinds of networks should really be trying to explore the possibility of truly planning and acting together.
39 It's a really interesting point, and that article is well worth reading. You know, one precedent for this might be how C40 Cities reacted early in 2020 to COVID because, under the leadership of Mayor Garcetti, the then-chair, and Mayor Sala from Milan, C40 Cities actually worked together in quite detailed ways. One way I remember very clearly is Seoul helped Seattle learn how to do drive-in testing for COVID because Seoul was ahead of Seattle.
And, although that's a different crisis, it does speak to the possibility of the collaboration you're speaking to. But, just on that point, you mentioned wildfires. You know, I'm in Canada. It was horrific what was happening here. We saw New York, Philadelphia, Boston, Toronto, Montreal working together last year during the wildfires because they were all receiving smoke from thousands of kilometres away.
There are floods, there's heat, there's increasing evidence of the spread of disease, potentially because of climate. One question people have is, "How bad is it going to get?" and, as a scientist, perhaps you have some insight. Are we close to tipping points? What is a tipping point in the context of climate change?
06 I think the tipping point is the moment or a critical threshold when a small change or series of small changes become really significant enough to actually cause a larger and often dramatic change, and it's likely it's a point of no return. And, once you have crossed a tipping point, things can't really easily go back to how they were functioning before and there is a new set of conditions or realities to really handle.
So, once you have crossed these tipping points, they are very often irreversible. If you look at climate-related tipping points, according to the analysis of David McKay, who is also a research fellow at Earth Commission, four to five major tipping points are already at risk of crossing due to the warming right now, and before, even we crossed the 1.5 degrees. So, what does crossing this tipping point mean for the Earth system?
For example, the collapse of the Greenland ice sheet, it is melting at an accelerated pace, and Greenland melting is changing the Atlantic Ocean current, which really actually controls the thermostat of Europe. And, this can be irreversible. And, the changing Atlantic Ocean current reduces the rainfall over the Amazon rainforest, which is now dying out and losing its ability to store carbon.
And, the Atlantic circulation is also linked to the collapse of part of the Western Antarctic ice sheet and Antarctica, which would dramatically raise the sea-level rise. And, we know that scientists think that, if the Greenland ice sheet is melted completely, that would contribute to more than 7 metres of sea-level rise to the world's oceans. And, just think about many of our cities, you know, located along the coast and river mouth, and many of them are often just above the sea level.
So, in short, I think the Greenland ice sheet tipping point being crossed means it might be set into a process of an irreversible domino effect across several other systems as well, with really, really devastating socioeconomic impacts.
13 [somber music] At C40, we've experienced, over the past few years, a huge increase in abuse online and very strange theories. You know, we work a lot around urban spatial planning, particularly the idea of the 15-minute city, so cities that are relatively compact and people can go about and get their daily needs met without having to own a car. And, it's become a huge, in some circles, conspiracy theory. It's bizarre, but some of this verges onto abuse. Two questions.
One – as a prominent climate scientist, is this something you're concerned about, personally? And secondly – how do we ensure that scientists feel safe to speak up and share their knowledge publicly and ensure that we can, you know, benefit from the knowledge and make the change that's needed before it's too late?
05 Indeed. I think more vocal climate scientists, including many women and many of them are my colleagues and friends, they became the subject of vicious attacks on the internet, and some even received death threats. One example of that is Will Steffen, who passed away last year and who was a world-renowned Earth system scientist here at ANU, and who was a prominent advocate for climate actions.
He really suffered from such threats to the extent that, when he was the director of the Australian National University Climate Institute, the corridor that led to his office had to be installed with a security door, and we know that many female climate scientists said they have received threats relating specifically to their gender.
And, I think this is, in a way, a phenomenon of our deeply polarized society and associated to the radicalization of some people, and I think more support and positive voices from society is really, really crucial. I can see several things that probably can be done. For example, we really need to realize that scientists are people who are trying to find out how things would work and communicate their findings and sound the alarm, based on what they have found.
And, what to do about this information is very often the choice of society, and attacking the canary in the mine doesn't really solve the gas-leaking problem of your mind. So, that's a very important thing, I think, for us all to remember. And, I think we need a very clear and unequivocal stance from our leaders across all the spectrum that, even if one disagrees with one another, such behaviour of abusing and threatening is really, really unacceptable.
People should know this by now, but I think it is important that our political leaders actually voice a clear voice in that, and I think they also need to be very, very careful not to really propel the misinformation and hatred in society. The general public also has a role to play here, for example, shaping a very strong consensus as a society for which the silent majority probably needs to step up a bit and voice their support for scientists who are trying to uncover the truth.
23 [driving music] Well, one of the things that gives me hope about the city-based climate movement is not just the technical aspects we've discussed. It's more along the lines of the culture, and I think it speaks to the point you just made about we have to create an environment where scientists and knowledge are respected and speak up when we see hatred or abuse being spread.
And, mayors reach across national boundaries sometimes when the national governments aren't speaking, and it gives me hope because it sets a standard for civility. You model them in your own behaviour, Professor, and it's been a delight to have you on Cities 1.5.
07 Thank you very much, David [music ends]
12 [upbeat, energetic music] As climate impacts rise beyond the models projected by scientists, our planet is forced into completely unknown territory. What we do know is that the need to urgently shift from dirty, polluting fossil fuels to clean, renewable sources has never been greater. Despite significant pushback from petrostates and the fossil fuel industry, COP28 closed with a final agreement that signalled a transition away from fossil fuels.
This is thanks, at least in part, to the voices ringing out from cities. By forming coalitions and demanding to be heard at the highest of levels, they are showing that they can influence their nation-states to act. Cities are at the forefront of climate action, but they are also the frontline of climate breakdown. The work of mayors has never been more vital. [music ends]
[Cities 1.5 main theme plays] On the next episode, we revisit a topic that's at the heart of Cities 1.5 and the Journal of City Climate Policy and Economy – ecological economics, which is a theory that privileges people and the planet over growth, a very different framework than the one most of our planet currently runs on.
Professor Peter Victor is a world-leading expert who recently published an article in the Journal on one of the founding thinkers of ecological economics, titled Herman Daly's Great Debates. Tune in next week. You won't want to miss it. [music continues] This has been Cities 1.5, leading global change through local climate action. I'm David Miller. I was the Mayor of Toronto, Canada, and I know, firsthand, the role cities can play in solving the climate crisis.
I'm the Editor in Chief of the Journal of City Climate Policy and Economy, published by the University of Toronto Press in collaboration with the C40 Centre for City Climate Policy and Economy, where I'm also the Managing Director. C40's mission is to help our member cities halve their emissions within a decade, while improving equity, building resilience, and creating the conditions for everyone, everywhere to thrive.
[music continues] Cities 1.5 is produced by University of Toronto Press in association with the Journal of City Climate Policy and Economy and C40 Cities. This podcast is produced by Jessica Schmidt, and our executive producers are Peggy Whitfield and Dali Carmichael. Our music is by Lorna Gilfedder. The fight for an equitable and resilient world is closer than you think. To learn more, visit the show's website, linked in the episode notes. See you next time.
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